The present invention relates to a method for performing reproduction on a video reproducing apparatus of signals stored on a disk reproducing apparatus.
Disk reproducing apparatus such as video disk players are usually installed in the vicinity of a video reproducing apparatus, such as a television receiver or a color monitor. The response of current disk reproducing apparatus to user manual control is so rapid that when the user sets the disk reproducing apparatus in a reproduction mode by a keying operation, the reproduction of video information will start before he has moved to a position suitable for viewing the video reproducing apparatus. Accordingly, the user will find it impossible to watch the recorded video information, such as a motion picture, from the very beginning of the disk. This problem could be solved if the reproduction mode where initiated by remote control with the recording disk being set in a pause mode at the starting end of the program area of the disk. However in the prior art, the disk may be set in a pause mode only in response to a pause command issued during the reproduction mode. Clearly, if the disk must be in reproduction mode, information is already being reproduced when the pause command is issued This makes it difficult to attain a pause mode at the starting end of the program area of the disk and inhibits the users ability to view the recorded information (such as a motion picture) from the very beginning of the disk.
There are two kinds of recording disks in common use, namely, a CAV (constant angular velocity) disk and a CLV (constant linear velocity) disk. In a CAV disk, all of the concentric tracks formed have video information of a constant amount, say, one frame, recorded along its circumference, and the interframe portions carrying information associated with a vertical sync signal lie on a straight line extending in tee radial direction. Therefore, with a CAV disk, no irregularity will be introduced in the period of sync signals for the video signal reproduced immediately after a jumping operation is performed i.e. a shift from one track to another. This permits a special mod of reproduction, such as one for producing a still picture, to be effected in a satisfactory manner.
In a CLV disk, the amount of information recorded on the circumference of a specific track varies with its radial position and the innermost track contains a small amount of video information, say, one frame, whereas the outermost track contains a greater amount of video information say, three frames. Because of this variation, an irregularity is introduced in the period of sync signals for the video signal reproduced immediately after a jumping operation. In order to eliminate this problem, an improved type of information reproducing apparatus has been proposed. This apparatus is equipped with a video memory having a capacity for storing video signals corresponding to one frame or field. The video signals being reproduced are successively converted into digital signals in response to clock signals synchronous with those video signals and the resulting digital signals are written at preselected locations in the video memory and read out therefrom in response to external stable clock signals.
In order to ensure that, after the reproduction of a still picture is terminated, subsequent pictures will be immediately reproduced, this improved type of apparatus may be so designed that disk rotation and a jumping function can be performed during the reproduction of a still picture. However, this is not a recommended practice since the motors, actuators and some other components will inevitably wear as a result of prolonged reproduction of still pictures.
Commercial video disks have a maximum playing time of 1 hour per side. On occasion, the user may wish to interrupt the viewing of a motion picture or some other video information on the video disk while it is still in a play mode. If the user wants to see the subsequent portion of the video information after this interruption, he may search for the last scene he was viewing by performing a FF (i.e., scanning) operation on the disk reproducing apparatus. The FF operation involves alternately performing playing and track jumping actions. However, this searching procedure involves a cumbersome series of operations.
The purpose of the present invention to overcome these operational difficulties encountered in the prior art of disk reproducing apparatus.
A first object, therefore, of the present invention is to provide a method that is capable of setting a disk reproducing apparatus in a pause mode at the starting end of the program area of a disk being played.
A second object of the present invention is to provide a method by which a still picture can be reproduced from a disk reproducing apparatus, having a video memory, without causing excessive wear of motors, actuators and any other components.
A further object of the present invention is to provide a method that requires only a simple set of operations for reproducing at the beginning of a current reproduction mode the last scene that was being viewed on a disk reproducing apparatus during a previous reproduction mode that was interrupted.